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1.
Small ; 19(19): e2206408, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36759965

RESUMO

Developing nanomedicines with superior reactive oxygen species (ROS) scavenging capability has emerged as a promising strategy in treating ROS-related diseases, for example, drug-induced liver injury. However, designing nanoscavengers with the self-propelling ability to scavenge ROS actively remains challenging. Here, a self-propelled silica-supported ultrasmall gold nanoparticles-tannic acid hybrid nanozyme (SAuPTB) is designed that can effectively alleviate acetaminophen (APAP)-induced liver injury by scavenging excessive ROS and regulating inflammation. SAuPTB exhibits multienzyme activity and displays significantly enhanced diffusion under hydrogen peroxide (H2 O2 ). This in vitro research shows that SAuPTB can effectively eliminate ROS, increasing the viability of H2 O2 -stimulated cells and reducing the cytotoxicity of APAP/H2 O2 -treated AML12 cells. The in vivo studies show that SAuPTB can accumulate at inflammatory sites in mouse liver, resulting in the decrease of alanine aminotransferase, aspartate aminotransferase, and ROS, reduction in pro-inflammatory cytokines and chemokines, hence reduced hepatocyte necrosis, liver injury, and mortality. Furthermore, SAuPTB activates the nuclear erythroid 2-related factor 2 pathway to upregulate antioxidative genes and reduce oxidative stress. Finally, the liver shows decreased high mobility group box 1 and F4/80+ macrophages, suggesting an anti-inflammatory response. This work provides a novel design strategy of nanozymes for ROS-related disease treatment.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Nanopartículas Metálicas , Animais , Camundongos , Acetaminofen/farmacologia , Anti-Inflamatórios/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Ouro , Espécies Reativas de Oxigênio/metabolismo
2.
Pestic Biochem Physiol ; 197: 105695, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38072550

RESUMO

Nuclear receptors play a crucial role in various signaling and metabolic pathways, such as insect molting and development. Buprofezin (2-tert-butylimino-3-isopropyl-5-phenyl-perhydro-1, 3, 5-thiadiazin-4-one), a chitin synthesis inhibitor, causes molting deformities and slow death in insects by inhibiting chitin synthesis and interfering with their metabolism. This study investigated whether buprofezin affects insect ecdysteroid signaling pathway. The treatment of buprofezin significantly suppressed the transcription levels of SfHR3 and SfHR4, two nuclear receptor genes, in third-instar nymphs of Sogatella furcifera. Meanwhile, the transcription levels of SfHR3 and SfHR4 in first-day fifth-instar nymphs were induced at 12 h after 20E treatment. In addition, the silencing of SfHR3 and SfHR4 genes in first-day fifth-instar nymphs caused severe developmental delay and molting failure, resulting in a significant reduction of survival rates at 7.36% and 2.99% on the eighth day, respectively. Further analysis showed that the silencing SfHR3 and SfHR4 significantly inhibited the transcription levels of chitin synthesis and degradation-related genes. These results indicate that buprofezin can inhibits chitin synthesis and degradation by suppressing the signal transduction of 20E through SfHR3 and SfHR4, leading to molting failure and death. This study not only expands our understanding of the molecular mechanism of buprofezin in pest control but also lays a foundation for developing new control strategies of RNAi by targeting SfHR3 and SfHR4.


Assuntos
Hemípteros , Muda , Animais , Muda/genética , Hemípteros/metabolismo , Insetos , Receptores Citoplasmáticos e Nucleares/metabolismo , Quitina/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo
3.
Insect Mol Biol ; 31(6): 798-809, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35899838

RESUMO

Sogatella furcifera is one of the most serious insect pests that affect rice in Asia. One class of small RNAs (sRNAs; ~22 nt long) is miRNAs, which participate in various biological processes by regulating the expression of target genes in a spatiotemporal manner. However, the role of miRNAs in nymph-to-adult transition in S. furcifera remains unknown. In this study, we sequenced sRNA libraries of S. furcifera prepared from individuals at three different developmental stages (pre-moult, moulting and early adult). A total of 253 miRNAs (134 known and 119 novel) were identified, of which 12 were differentially expressed during the nymph-to-adult developmental transition. Moreover, Real time quantitative PCR (RT-qPCR) analysis revealed that all 12 miRNAs were differentially expressed among five different nymph tissues and 14 different developmental stages (first to fifth instar nymphs and 1-day-old adults). Injection of miR-2a-2 mimic/antagomir and miR-305-5p-1 mimic/antagomir into 1-day-old fifth instar nymphs significantly increased the mortality rate. In addition, a defective moulting phenotype was observed in nymphs injected with miR-2a-2 and miR-305-5p-1, suggesting that these miRNAs are involved in S. furcifera nymph-adult transition. In conclusion, these results reveal the function of critical miRNAs in S. furcifera nymph-adult transition, and also provide novel potential targets of insecticides for the long-term sustainable management of S. furcifera.


Assuntos
Hemípteros , Inseticidas , MicroRNAs , Animais , Ninfa/genética , Antagomirs , Hemípteros/genética
4.
Eur J Nucl Med Mol Imaging ; 49(7): 2310-2322, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35044495

RESUMO

PURPOSE: To specifically diagnose malignant tumors in DWI using the human telomerase reverse transcriptase (hTERT) promoter-driven AQP1 expression. METHODS: The human telomerase reverse transcriptase (hTERT) promoter-driven AQP1 gene overexpression lentivirus system (hTERT-AQP1) and cytomegalovirus (CMV) promoter-driven AQP1 gene overexpression lentivirus system (CMV-AQP1) were prepared, and transduced into telomerase-positive and -negative cells. The AQP1 expression and DWI signal intensity (SI) change in transduced cells were analyzed. Balb/C nude mice subcutaneous xenograft models derived from lentivirus-transduced telomerase-positive and -negative cells were used to evaluate AQP1 expression and DWI SI change in vivo. We further established another group of subcutaneous xenograft model using pristine telomerase-positive and -negative cells, followed by injecting the lentiviral vectors intratumorally or intravenously, to determine the malignant tumor-targeted imaging of hTERT-AQP1. RESULTS: The hTERT-AQP1 and CMV-AQP1 were successfully prepared. After transduction, hTERT-AQP1 could induce the specific overexpression of AQP1 in telomerase-positive cells. Compared with untransduced cells, all CMV-AQP1-pretransduced cells and hTERT-AQP1-pretransduced telomerase-positive cells showed decreased SI and increased apparent diffusion coefficient (ADC) in DWI, while hTERT-AQP1-pretransduced telomerase-negative cells showed no obvious SI and ADC change. Correspondingly, hTERT-AQP1-transduced telomerase-positive tumors and CMV-AQP1-transduced telomerase-positive and -negative tumors showed decreased DWI SI and increased ADC, while hTERT-AQP1-transduced telomerase-negative tumor had no SI and ADC changes. After intratumoral or intravenous injection, CMV-AQP1 could upregulate AQP1 expression and induce DWI SI and ADC alteration in both telomerase-positive and -negative tumors, while hTERT-AQP1 worked in telomerase-positive tumors specifically. CONCLUSION: Cancers can be specifically visualized based on the DWI signal alteration which triggered by hTERT-AQP1 lentivirus system that combined AQP1 gene and hTERT promoter.


Assuntos
Infecções por Citomegalovirus , Neoplasias , Telomerase , Animais , Aquaporina 1/genética , Aquaporina 1/metabolismo , Linhagem Celular Tumoral , Infecções por Citomegalovirus/genética , Humanos , Camundongos , Camundongos Nus , Neoplasias/diagnóstico por imagem , Neoplasias/genética , Regiões Promotoras Genéticas , Telomerase/genética , Telomerase/metabolismo
5.
Pestic Biochem Physiol ; 173: 104779, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33771258

RESUMO

The isoprene branching pathway is a unique downstream synthesis pathway of juvenile hormone (JH) in arthropods, which plays an important role in the growth, development, and reproduction of insects. Juvenile hormone acid O-methyltransferase (JHAMT) and farnesoic acid O-methyltransferase (FAMeT) are two key proteins that are regulated in the isoprene branching pathway. Based on the available transcriptomic and genomic data of Sogatella furcifera, full-length cDNAs of SfJHAMT and SfFAMeT were identified. In vitro injection of dsRNA targeted to silence SfJHAMT and SfFAMeT inhibited the fecundity, ovarian development, and transcription levels of SfKr-h1 and SfVg significantly. Of note, The transcription levels of SfJHAMT and SfFAMeT are regulated mutually; i.e., silencing of SfJHAMT causes an increase in the SfFAMeT transcription level and vice versa, and the negative effect of simultaneous silencing on reproduction is greater. The results revealed a coordinated effect of SfJHAMT and SfFAMeT on the reproductive capabilities of S. furcifera. Furthermore, a JH analog (methoprene) partially rescued the negative effect of simultaneous silencing by SfJHAMT and SfFAMeT on reproduction. In addition, the expression profile analysis after insecticide stress showed that triazophos (LC25) can induce the transcription of SfMet and SfKr-h1 to promote JH signal transduction, which affects the transcription of SfVg and ultimately promotes the reproduction of S. furcifera. The results of the present study lay a foundation to further explain the isoprene branch pathway function in insect reproduction and can open up new avenues for sustainable pest control while expanding the current understanding of molecular mechanisms through which insecticides stimulate reproduction and lead to pest resurgence.


Assuntos
Hemípteros , Inseticidas , Animais , Fertilidade , Inseticidas/toxicidade , Hormônios Juvenis , Reprodução
6.
J Insect Sci ; 21(4)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34333649

RESUMO

Chitin deacetylases (CDAs) are chitin-degrading enzymes that play a key role in insect molting. In this study, we identified and characterized four full-length cDNAs of CDAs from Sogatella furcifera (Horváth). Developmental expression showed that SfCDA1 and SfCDA2 were expressed at all nymph developmental stages, SfCDA3 and SfCDA4 were mainly expressed in the third-instar to fifth-instar nymph stages, whereas tissue-specific analyses indicated that four CDA genes were mainly high expressed in the integument and head during the fifth-instar nymph. RNA interference (RNAi) results revealed that SfCDA1, SfCDA2, and SfCDA4 are associated with molting defect and high mortality with nymph-adult molting. Furthermore, transcripts of chitin synthase 1 variants (SfCHS1, SfCHS1a, and SfCHS1b) were significantly downregulated and causing significant changes in the expression levels of trehalases (TRE1 and TRE2) in the SfCDA1, SfCDA2, and SfCDA4 dsRNA treatment groups. By contrast, no significant phenotypic characteristics were observed after dsSfCDA3 injection. Taken together, our results suggest that SfCDA1, SfCDA2, and SfCDA4 play a vital role in nymph-adult transition, and these genes could regulate chitin biosynthesis expression levels.


Assuntos
Amidoidrolases/genética , Hemípteros , Animais , Quitina/biossíntese , Quitina/genética , DNA Complementar , Genes de Insetos , Hemípteros/genética , Proteínas de Insetos/genética , Muda/genética , Ninfa/genética , Filogenia , Interferência de RNA , Asas de Animais/crescimento & desenvolvimento
7.
Nano Lett ; 19(5): 3011-3018, 2019 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-30971089

RESUMO

Magnetic/plasmonic hybrid nanoparticles are highly desirable for multimodal bioimaging and biosensing. Although the synthesis of heterodimeric nanoparticles has been reported, the products are usually hydrophobic so that post-treatment procedures are required to transfer them into water which are often difficult to perform and cause damages to the structures. Direct synthesis of hydrophilic hybrid nanostructures has remained a grand challenge albeit its immediate advantage of biocompatibility. Herein we report a general seed-mediated approach to the synthesis of hydrophilic and biocompatible M-Fe3O4 (M = Au, Ag, and Pd) heterodimers, in which the size of metals and Fe3O4 can be independently regulated in a wide range. Benefiting from the aqueous synthesis, this approach can be further extended to design more complex heterodimeric structures such as AgPtalloy-Fe3O4, Aucore@Pdshell-Fe3O4, and Aushell-Fe3O4. The hydrophilic nature of our heterodimers makes them readily useful for biomedical applications without the need of additional ligand exchange processes in contrast to those prepared in nonpolar solvents. These nanoscale magnetic/plasmonic heterostructures were shown to be ideally suited for integrated biomedical diagnoses, such as magnetic resonance imaging, photoacoustic imaging, optical coherence tomography, and computed tomography, in virtue of their biocompatibility and combined tunable magnetic and plasmonic properties.


Assuntos
Meios de Contraste/farmacologia , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/química , Imagem Multimodal/métodos , Meios de Contraste/química , Ouro/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Tomografia Computadorizada por Raios X , Água/química
8.
BMC Cancer ; 17(1): 335, 2017 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-28514957

RESUMO

BACKGROUND: Lymphatic vessel density and lymphovascular invasion are commonly assessed to identify the clinicopathological outcomes in breast cancer. However, the prognostic values of them on patients' survival are still uncertain. METHODS: Databases of PubMed, Embase, and Web of Science were searched from inception up to 30 June 2016. The hazard ratio with its 95% confidence interval was used to determine the prognostic effects of lymphatic vessel density and lymphovascular invasion on disease-free survival and overall survival in breast cancer. RESULTS: Nineteen studies, involving 4215 participants, were included in this study. With the combination of the results of lymphatic vessel density, the pooled hazard ratios and 95% confidence intervals were 2.02 (1.69-2.40) for disease-free survival and 2.88 (2.07-4.01) for overall survival, respectively. For lymphovascular invasion study, the pooled hazard ratios and 95% confidence intervals were 1.81 (1.57-2.08) for disease-free survival and 1.64 (1.43-1.87) for overall survival, respectively. In addition, 29.56% (827/2798) of participants presented with lymphovascular invasion in total. CONCLUSIONS: Our study demonstrates that lymphatic vessel density and lymphovascular invasion can predict poor prognosis in breast cancer. Standardized assessments of lymphatic vessel density and lymphovascular invasion are needed.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Vasos Linfáticos/patologia , Intervalo Livre de Doença , Feminino , Humanos , Linfangiogênese/fisiologia , Metástase Linfática , Invasividade Neoplásica/patologia , Modelos de Riscos Proporcionais
9.
Eur Radiol ; 26(11): 4089-4097, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26960542

RESUMO

OBJECTIVES: Using the human telomerase reverse transcriptase (hTERT) promoter and the modified ferritin heavy chain (Fth) reporter gene, reporter gene expression for MRI was examined in telomerase positive and negative tumour cells and xenografts. METHODS: Activity of the reporter gene expression vector Lenti-hTERT-Fth1-3FLAG-Puro was compared to constitutive CMV-driven expression and to the untransfected parental control in five tumour cell lines: A549, SKOV3, 293T, U2OS and HPDLF. In vitro, transfected cells were evaluated for FLAG-tagged protein expression, iron accumulation and transverse relaxation. In vivo, tumours transduced by lentiviral vector injection were imaged using T2*WI. Changes in tumour signal intensity were validated by histology. RESULTS: Only telomerase positive tumour cells expressed FLAG-tagged Fth and displayed an increase in R2* above the parental control, with a corresponding change in T2*WI. In addition, only telomerase positive tumours, transduced by injection of the reporter gene expression construct, exhibited a change in signal intensity on T2*WI. Tumour histology verified the expression of FLAG-tagged Fth and iron accumulation in telomerase positive tissue. CONCLUSION: Reporter gene expression for MRI, using the Fth reporter and the hTERT promoter, may be a useful strategy for the non-invasive diagnosis of many types of cancer. KEY POINTS: • Modified heavy chain of ferritin can serve as an MR reporter gene • hTERT promoter can direct the expression of reporter gene in cancer cells • MR reporter imaging mediated by hTERT promoter can be used for cancer diagnosis.


Assuntos
Apoferritinas/metabolismo , Imagem Molecular/métodos , Neoplasias/diagnóstico , Telomerase/metabolismo , Análise de Variância , Animais , Apoferritinas/genética , Linhagem Celular Tumoral , Genes Reporter/genética , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética/métodos , Masculino , Camundongos Endogâmicos BALB C , Regiões Promotoras Genéticas/genética , Telomerase/genética , Transfecção/métodos
10.
J Nanobiotechnology ; 13: 24, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25890315

RESUMO

BACKGROUND: GoldMag nanoparticles (GMNPs) possess the properties of colloid gold and superparamagnetic iron oxide nanoparticles, which make them useful for delivery, separation and molecular imaging. However, because of the nanometer effect, GMNPs are highly toxic. Thus, the biosafety of GMNPs should be fully studied prior to their use in biomedicine. The main purpose of this study was to evaluate the nanotoxicity of GMNPs on human umbilical vein endothelial cells (HUVECs) and determine a suitable size, concentration and time for magnetic resonance imaging (MRI). RESULTS: Transmission electron microscopy showed that GMNPs had a typical shell/core structure, and the shell was confirmed to be gold using energy dispersive spectrometer analysis. The average sizes of the 30 and 50 nm GMNPs were 30.65 ± 3.15 and 49.23 ± 5.01 nm, respectively, and the shell thickness were 6.8 ± 0.65 and 8.5 ± 1.36 nm, respectively. Dynamic light scattering showed that the hydrodynamic diameter of the 30 and 50 nm GMNPs were 33.2 ± 2.68 and 53.12 ± 4.56 nm, respectively. The r 2 relaxivity of the 50 nm GMNPs was 98.65 mM(-1) s(-1), whereas it was 80.18 mM(-1) s(-1) for the 30 nm GMNPs. The proliferation, cytoskeleton, migration, tube formation, apoptosis and ROS generation of labeled HUVECs depended on the size and concentration of GMNPs and the time of exposure. Because of the higher labeling rate, the 50 nm GMNPs exhibited a significant increase in nanotoxicity compared with the 30 nm GMNPs at the same concentration and time. At no more than 25 µg/mL and 12 hours, the 50 nm GMNPs exhibited no significant nanotoxicity in HUVECs, whereas no toxicity was observed at 50 µg/mL and 24 hours for the 30 nm GMNPs. CONCLUSIONS: These results demonstrated that the nanotoxicity of GMNPs in HUVECs depended on size, concentration and time. Exposure to larger GMNPs with a higher concentration for a longer period of time resulted in a higher labeling rate and ROS level for HUVECs. Coupled with r 2 relaxivity, it was suggested that the 50 nm GMNPs are more suitable for HUVEC labeling and MRI, and the suitable concentration and time were 25 µg/mL and 12 hours.


Assuntos
Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dextranos/química , Relação Dose-Resposta a Droga , Ouro/química , Células Endoteliais da Veia Umbilical Humana/química , Humanos , Magnetismo , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/toxicidade , Microscopia Eletrônica de Transmissão , Neovascularização Fisiológica/efeitos dos fármacos , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo
11.
Pak J Pharm Sci ; 27(4 Suppl): 1089-92, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25016271

RESUMO

Hemsleya sinesis Cogn has a variety of medicinal value. Strain KLXD06 is an endophytic bacteria isolated from H. sinesis exhibited significant inhibitory activity against methicillin-resistant Staphylococcus aureus (MRSA). This strain was identified by methods including 16S rDNA sequence homology and phylogenetic analysis morphological, biochemical and physiological characteristics analysis. Ccrude protein from KLXD06 was extracted by ammon ium sulfate salting-out. The results showed that strain KLXD06 was identified as Serratia marcescens. Antibacterial crude protein from KLXD06 was extracted by ammon ium sulfate salting-out, has a thermal stability.


Assuntos
Proteínas de Bactérias/farmacologia , Cucurbitaceae/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Serratia marcescens/química , Filogenia , Serratia marcescens/classificação , Serratia marcescens/isolamento & purificação
12.
Pest Manag Sci ; 80(4): 1912-1923, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38088492

RESUMO

BACKGROUND: The white-backed planthopper (WPH), Sogatella furcifera (Horváth), is a destructive rice pest with strong reproductive capacity. To gain insights into the roles of chitinases in the reproductive process of this insect species, this study represents the first-ever endeavor to conduct an in-depth exploration into the reproductive functions of four chitinase genes. RESULTS: In this study, it was observed that four chitinase genes were expressed in female adults, with a relatively high expression level in the ovaries. SfCht2 and SfIDGF1 were highly expressed during later ovarian development. while SfENGase increased and then decreased with ovarian development. SfCht2, SfCht6-2 and SfENGase were highly expressed in fat body on the first and second days after eclosion, whereas SfIDGF1 highest on day 7. Compared with control group, Silencing four chitinase genes inhibited ovarian development and significantly shortened the oviposition period of S. furcifera, reducing egg-laying capacity but not affecting egg hatching. The detection demonstrated that the expression levels of SfVg, SfVgR and 70-90% juvenile hormone (JH) signaling pathway-related reproductive genes was significantly down-regulated. Moreover, SfCht6-2 and SfENGase significantly affected the expression levels of Target of Rapamycin (TOR) signaling pathway genes. SfENGase had the ability to impact nutrient signaling pathways and fatty acid metabolism, repressing vitellogenin synthesis and ultimately influencing ovarian development of S. furcifera. CONCLUSIONS: Overall, this study provides insight into the function of chitinases in insect fecundity and is of great significance for enriching the cognition of insect chitinase function. They will become the suitable target genes for controlling the most destructive rice planthoppers. © 2023 Society of Chemical Industry.


Assuntos
Quitinases , Hemípteros , Feminino , Animais , Quitinases/genética , Quitinases/farmacologia , Reprodução/genética , Fertilidade/genética , Oviposição/genética
13.
Int J Nanomedicine ; 18: 7901-7922, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38148856

RESUMO

Acute liver injury (AIL), a fatal clinical disease featured with a swift deterioration of hepatocyte functions in the short term, has emerged as a serious public health issues that warrants attention. However, the effectiveness of existing small molecular antioxidants and anti-inflammatory medications in alleviating AIL remains uncertain. The unique inherent structural characteristics of liver confer it a natural propensity for nanoparticle capture, which present an opportunity to exploit in the formulation of nanoscale therapeutic agents, enabling their selective accumulation in the liver and thereby facilitating targeted therapeutic interventions. Significantly increased reactive oxygen species (ROS) accumulation and inflammation response have been evidenced to play crucial roles in occurrence and development of AIL. Nanozymes with ROS-scavenging capacities have demonstrated considerable promise in ROS elimination and inflammation regulation, thereby offering an appealing therapeutic instrument for the management of acute liver injury. In this review, the mechanisms of different type of ALI were summarized. In addition, we provide a comprehensive summary and review of the available ROS-scavenging nanozymes, including transition metal-based nanozymes, noble metal nanozymes, carbon-based nanozymes, and some other nanozymes. Furthermore, the challenges still need to be solved in the field of ROS-scavenging nanozymes for ALI alleviation are also discussed.


Assuntos
Hepatócitos , Fígado , Humanos , Espécies Reativas de Oxigênio , Inflamação , Antioxidantes
14.
Regen Biomater ; 9: rbac037, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784095

RESUMO

Central nervous system (CNS) injury, induced by ischemic/hemorrhagic or traumatic damage, is one of the most common causes of death and long-term disability worldwide. Reactive oxygen and nitrogen species (RONS) resulting in oxidative/nitrosative stress play a critical role in the pathological cascade of molecular events after CNS injury. Therefore, by targeting RONS, antioxidant therapies have been intensively explored in previous studies. However, traditional antioxidants have achieved limited success thus far, and the development of new antioxidants to achieve highly effective RONS modulation in CNS injury still remains a great challenge. With the rapid development of nanotechnology, novel nanomaterials provided promising opportunities to address this challenge. Within these, nanoceria has gained much attention due to its regenerative and excellent RONS elimination capability. To promote its practical application, it is important to know what has been done and what has yet to be done. This review aims to present the opportunities and challenges of nanoceria in treating CNS injury. The physicochemical properties of nanoceria and its interaction with RONS are described. The applications of nanoceria for stroke and neurotrauma treatment are summarized. The possible directions for future application of nanoceria in CNS injury treatment are proposed.

15.
ACS Nano ; 16(1): 910-920, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35023718

RESUMO

Plasmonic nanomaterials with strong absorption at near-infrared frequencies are promising photothermal therapy agents (PTAs). The pursuit of high photothermal conversion efficiency has been the central focus of this research field. Here, we report the development of plasmonic nanoparticle clusters (PNCs) as highly efficient PTAs and provide a semiquantitative approach for calculating their resonant frequency and absorption efficiency by combining the effective medium approximation (EMA) theory and full-wave electrodynamic simulations. Guided by the theoretical prediction, we further develop a universal strategy of space-confined seeded growth to prepare various PNCs. Under optimized growth conditions, we achieve a record photothermal conversion efficiency of up to ∼84% for gold-based PNCs, which is attributed to the collective plasmon-coupling-induced near-unity absorption efficiency. We further demonstrate the extraordinary photothermal therapy performance of the optimized PNCs in in vivo application. Our work demonstrates the high feasibility and efficacy of PNCs as nanoscale PTAs.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , Ouro , Terapia Fototérmica , Fototerapia , Nanopartículas Metálicas/uso terapêutico
16.
Insects ; 13(2)2022 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-35206747

RESUMO

The juvenile hormone (JH) is crucial for insect reproduction, and isopentenyl pyrophosphate isomerase (IPPI) is a key enzyme in the JH synthesis pathway. However, few studies have investigated how IPPI regulates insect reproduction. This study identifies and characterizes the IPPI gene (SfIPPI) from the important agricultural pest Sogatella furcifera. A phylogenetic analysis reveals a high homology of SfIPPI with the IPPI amino acid sequences of Laodelphax striatellus and Nilaparvata lugens (Stål). Furthermore, SfIPPI is expressed at various developmental stages and in various tissues of S. furcifera, and is significantly higher on the 5th day of adult emergence and in integument tissue, while lower levels are found on the 3rd day of adult emergence and in fat body and gut tissue. After silencing SfIPPI using RNA interference, the ovarian development is significantly inhibited and the fecundity is significantly reduced when compared with the control group. Additionally, SfIPPI silencing significantly decreases the expression levels of downstream JH signal transduction pathway genes (SfJHAMT, SfFAMeT, and SfKr-h1) and SfVg. Our findings are helpful in elucidating the molecular mechanism underlying the regulation of insect reproduction through genes in the JH synthesis pathway, and they provide a theoretical basis for the development of pest control treatments targeting SfIPPI.

17.
J Hazard Mater ; 436: 129140, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35594670

RESUMO

In this work, we developed an ultrasensitive colorimetry for Salmonella typhimurium detection with multifunctional Au-Fe3O4 dumbbell-like nanoparticles (DBNPs) which possessed easy bio-modifiability, excellent LSPR characteristics, superparamagnetic properties and super peroxidase-like activity. In the detection, the anti-S. typhimurium antibody modified DBNPs (IDBNPs) bound with S. typhimurium and aggregated on their surfaces in a large number, which showed much quicker magnetic response than free IDBNPs. By controlling appropriate separation conditions, IDBNPs@S. typhimurium composites were captured, while free IDBNPs were remained in the supernatant. Therefore, by detecting the absorbance of the supernatant, quantitative detection was achieved from 10 to 1000 CFU/mL. Moreover, utilizing the peroxidase-like activity of IDBNPs, we further realized semi-quantitative naked-eye detection. By adding ABTS into the above supernatant, which was oxidized to green chelate (OxABTS), colorimetric signal was amplified significantly, and meanwhile, the green chelates and the wine-red IDBNPs engendered mixed color, enhancing the range of color gradation and greatly improving the visual resolution. Finally, a detection limit (10 CFU/mL) comparable with that of above spectrum measurement was achieved. Besides, our method exhibited efficient capture capability (nearly 100% even for rare S. typhimurium), and had good stability and specificity, and acceptable anti-interference ability in fetal bovine serum and milk samples.


Assuntos
Nanopartículas Metálicas , Nanopartículas Multifuncionais , Colorimetria/métodos , Compostos Férricos , Ouro , Limite de Detecção , Magnetismo , Peroxidases , Salmonella typhimurium
18.
Molecules ; 16(12): 9775-82, 2011 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-22117168

RESUMO

Phytohemical investigation on the heartwood of Dalbergia odorifera resulted in the isolation of nine flavonoids. Their structures were elucidated as sativanone (1), (3R)-vestitone (2), (3R)-2',3',7-trihydroxy-4'-methoxyisoflavanone (3), (3R)-4'-methoxy-2',3,7-trihydroxyisoflavanone (4), carthamidin (5), liquiritigenin (6), isoliquiritigenin (7), (3R)-vestitol (8), and sulfuretin (9) based on their spectral data. All compounds were evaluated for their inhibitory activity against Ralstonia solanacearum. This is the first report about anti-R. solanacearum activity of the compounds from D. odorifera.


Assuntos
Antibacterianos/farmacologia , Dalbergia/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Ralstonia solanacearum/efeitos dos fármacos , Antibacterianos/química , Flavonoides/química , Testes de Sensibilidade Microbiana
19.
Int J Nanomedicine ; 16: 6383-6394, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34556986

RESUMO

BACKGROUND: Satisfactory prognosis of breast cancer (BC) is limited by difficulty in early diagnosis and insufficient treatment. The combination of molecular imaging and photothermal therapy (PTT) may provide a solution. METHODS: Fe3O4-Aushell nanoparticles (NPs) were prepared by thermal decomposition, seeded growth and galvanic replacement and were comprehensively characterized. After conjugated to PEG, NPs were used as MRI and PTT agents in vitro and in vivo. RESULTS: Fe3O4-Aushell NPs which had uniform Janus-like morphology were successfully synthesized. The Fe3O4 had a size of 18 ± 2.2 nm, and the Aushell had an outer diameter of 25 ± 3.3 nm and an inner diameter of 20 ± 2.9 nm. The NPs showed superparamagnetism, a saturation magnetization of 36 emu/g, and an optical absorption plateau from 700 to 808 nm. The Fe3O4-Aushell NPs were determined to possess good biocompatibility. After PEG coating, the zeta potential of NPs was changed from -23.75 ± 1.37 mV to -13.93 ± 0.55 mV, and the FTIR showed the characteristic C-O stretching vibration at 1113 cm-1. The NPs' MR imaging implied that the T2 can be shortened by Fe3O4-Aushell NPs in a concentration-dependent manner, and the Fe3O4-Aushell NPs coated with PEG at the molar ratio of 160 (PEG: NPs) showed the highest transverse relaxivity (r 2) of 216 mM-1s-1. After irradiation at 0.65 W/cm2 for 5 min, all cells incubated with the Fe3O4-Aushell-PEG160 NPs (Fe: 30 ppm, Au: 70 ppm) died. After administrated intratumorally, Fe3O4-Aushell-PEG160 notably decreased the signal intensity of tumor in T2WI images. Under the same irradiation, the temperature of tumors injected with Fe3O4-Aushell-PEG160 quickly rose to 54.6°C, and the tumors shrank rapidly and were ablated in 6 days. CONCLUSION: Fe3O4-Aushell-PEG NPs show good r 2 and PTT performance and are promising synergistic theranostic agents of MRI and PTT for BC.


Assuntos
Neoplasias da Mama , Nanoestruturas , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Feminino , Humanos , Imageamento por Ressonância Magnética , Terapia Fototérmica , Medicina de Precisão , Nanomedicina Teranóstica
20.
Front Aging Neurosci ; 13: 738679, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34955807

RESUMO

Background: The aging process and declining estradiol levels are two important factors that cause structural brain alterations. Many prior studies have investigated these two elements and revealed controversial results in menopausal women. Here, a cross-sectional study was designed to individually evaluate estradiol-related structural changes in the brain. Methods: A total of 45 early menopausal women and 54 age-matched premenopausal controls were enrolled and subjected to magnetic resonance imaging (MRI) scans, blood biochemistry tests, and neuropsychological tests. MRI structural images were analyzed using FreeSurfer to detect changes in subcortical and cortical volumes as well as cortical thickness. Finally, structural brain data as well as clinical and neuropsychological data were used for Pearson's correlation analyses to individually determine estradiol-related structural and functional changes in the brains of early menopausal women. Results: Compared with the premenopausal controls, the early menopausal women showed significant subcortical volumetric loss in the left amygdala and right amygdala, higher serum follicle-stimulating hormone (FSH) levels, more recognizable climacteric and depressive symptoms, decreased quality of sleep, and decreased working memory and executive functions. Simultaneously, FSH levels were related to lower working memory accuracy and longer working memory reaction time. Decreased subcortical volume in the bilateral amygdala was also related to lower working memory accuracy and longer executive reaction time in early menopausal women. Conclusion: The data suggest that estradiol deficiency in early menopausal women can lead to subcortical volume and functional brain changes, which may contribute to further understanding the neurobiological role of declined estradiol levels in early menopausal women.

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